Ever see a stand-up comic do an entire routine about stereotypical differences between men and women? Stretch that tired set of jokes out to some 75 minutes, put ’em in a weak sketch format, and you’ve got “Dave Barry’s Complete Guide To Guys.”

Written and directed by Jeff Arch, “Guys” is a loose adaptation of Barry’s book of the same name. I have not read the book - in fact, I have not read Barry’s writings in a very long time. I remember them being both very funny and very unfunny, often within the same article, a well-played turn of a phrase helping land a big laugh in the middle of generic-comedy observations. The movie’s the same way, more or less; a couple of guffaws sprinkled throughout a series of mediocre set-ups and anemic punchlines.

The film plays out as a mockumentary/sketch comedy combo pack. Barry, as himself, is our host, interviewing bumbling experts (all of whom are played by John Cleese, a joke that sadly wears thin too quickly) and frustrated women (these are passed off as actual interviews, but they’re so phony, scripted, and poorly acted that nobody’s bound to confuse them for the truth), and setting the scene for each kooky skit, all of which star Lochlyn Munro and Khalil Kain as the hapless, clueless guys, and Megan Ward and Christina Moore as their long-suffering girlfriends.

Barry is quick to point out the difference between “guys” and “men” (“The guys were funnier. The men were more responsible.”), a way of covering his bases and thwarting off attacks of being too general in his comedy. He’s also careful to avoid generalizations about women - a couple jokes about how they communicate so well with each other, but that’s about it.

There are a few good moments, the best of which is a skit in which Barry and Dan Marino, in sportscaster mode and with the help of a telestrator, explain the male ritual of staking out the correct urinal. By methodically pointing out every last detail of men’s public restroom habits in the guise of sports commentary and owning up to the ridiculousness of it all, the bit truly zings, becoming the smart, witty, and enjoyably silly chunk of observational humor that the rest of the film wishes it could be.

The rest of the successes are mostly in fleeting one-liners or odd reactions: one monologue cleverly replaces the word “orgasms” with the word “euphemisms;” another gets a laugh out of the word Visigoths, which is admittedly a very funny word.

And that’s the problem. Most of Barry’s humor is found in his wordplay, and Barry’s style of wordplay doesn’t translate well onto the screen, at least not here. Barry and Arch can try to squeak by with a clever sentence from time to time, but toss in some bad line readings from a weak cast (even Cleese fails to impress, as he’s mostly just sleepwalking through his routines) and the wordplay flops. To make up for this gap, the rest of the movie gets filled with cheap shots and barely-worth-a-grin ideas like flashbacks to Stone Age, with cavemen becoming impressed with their neighbors’ newest gadgets, and isn’t that just like guys today, ha ha?

Other gags fall apart because they get overcooked. Consider one joke that explains how “Concern Rays” emanating from male sports fans can help determine the outcome of a specific game. It’s a cute idea, and Barry’s faux-science explanation clicks at first. But comedy is all about timing, and this scene desperately needs a trim of at least one or two minutes, cutting out before the joke runs stale.

In fact, most of the jokes sag due to poor comic timing, which is odd, considering the movie runs a scant 75 minutes (just over 80 if you’re counting the credits). At such a short length, this thing should fly. Instead, it drags, with wimpy and repetitive material. There’s probably enough here to make for a halfway decent half-hour TV special. Yeah, Barry’s a nice enough guy to deserve his own half-hour TV special. But not a whole movie. Well, at least not this movie.